全新世臺灣南部珊瑚骨骼及軟體動物殼體穩定碳氧同位素記錄之研究

We have analyzed 178 stable isotope and Sr/Ca records of coral skeleton (9073 ± 78 BP ~8850 ± 60 BP), 214 stable isotope records of archaeological mollusk shells, and 141 stable hydrogen and oxygen isotope records of aquiculture water samples to reconstruct the Holocene paleoenviroment of southern Taiwan. Oxygen isotope values of coral skeleton are between -6.6? and -3.8? and the Sr/Ca ratios are between 8.3 and 9.8. Seasonal fluctuation are observed in both oxygen isotope and Sr/Ca records. However, annual temperature are estimated between 19.1°C and 34.0°C and between 14.7°C and 37.6°C using oxygen isotope records and Sr/Ca records, respectively. Difference in temperature estimation between these two methods need to be further studied. A total of 214 isotopic analyses were performed on archaeological oyster shells. In ascending order, average oxygen isotope values are -6.3 ± 1.7?, -6.5 ± 0.9?, and -6.8 ± 1.2? for Dabenkeng (5000~4200 B.P.), Niuchouzi (4200~3300 B.P.), and Dahu (3300~1800 B.P.) cultures, respectively. Mean oxygen isotope values of these three cultures are less than that of modern oyster shells (-3.1 ± 1.2?) indicating warmer/wet environment between 5000~1800 B.P. in southwestern Taiwan. Salinity of aquiculture water samples are between 6 psu to 36 psu during October, 2017 and September, 2018. Oxygen isotope values of water collected are between -9.8? and 0.5? and is positively correlated with salinity. Therefore, seasonal salinity and oxygen isotope variations are observed. These signals can be recorded in the mollusk shells and will be further studied.